When developing one roll of film in my two roll tank I tend to get varying results. Usually over developed or right on. Is this because of the extra room in the tank and the chemicals can move more vigorously? I don't like to wait too long to develop rolls, but maybe this is my best bet? I usually use TMax 100 in TMax developer at 68' for 7 min. and agitate 5 times every 30 sec. and get very good results (with 2 rolls). Maybe shorten the developing time? Janet

-- Janet Morley (photojanet2256@cs.com), December 15, 2001

Answers

Janet Try putting an empty reel on top. I have my students to one inversion each 30 seconds.

-- Ann C lancy (clancya@mediaone.net), December 15, 2001.

You can get very different agitation. Image a single roll tank (capacity of liquid=250mL) with a single roll, and developer almost up to the lid. Inverting this will, in effect, cause a bubble of about (I'm guessing here) 40mL to go through the film reel area and back again.

Now imaging the same film and quantity of liquid in a double sized tank. Tipping it upside down drains all of the liquid from the film.

This must result in much greater redistribution and maybe by draining the film, it hay have a greater effect of removing and replenishing the liquid in the emulsion of the film.

-- yevtushenko (jo.sto@bigpond.com), December 15, 2001.

You don't describe your technique (roller processing, inversion agitation, twirling agitation, how much developer you use, etc.) so we are just shooting in the dark, but:

If you using inversion or twirling agitation, you must put a blank reel above the full one to keep the full one in place.

Use only as much developer as is needed to cover the lower reel, assuming you're not at extremely weak dilution. This allows empty space for the development by-products to equally distribute when inverting.

With normal developers, using a two-reel tank, top reel empty, and only covering the lower reel with developer is my STANDARD method. I've always gotten consistent development.

By the way, use empty reels and add water to cover the lower reel. Measure how much water was needed to cover the lower reel, so you can go my measurement, not estimation, on how much developer is needed.

-- Charlie Strack (charlie_strack@sti.com), December 15, 2001.

Your agitation rate combined with only one reel is probably causing your problem.I suspect you have pretty contrasty negs! I agree with Ann, put another reel in the tank. I agitate 5 seconds every 30 seconds, as this is what works for me. The main thing however, is your consistency. Don't change more than one variable at a time.

-- Arden Howell (Serenisea@aol.com), December 15, 2001.

I never use two reels in a two reel Paterson System 4 tank when developing one film, which I do 99% (nearly always) of the time. I've never had a problem with the spool moving on the central column, it's a firm fit. I usually want the other spool dry so I can run another film straight away.

As far as agitation is concerned, I usually invert 3 times every minute, twisting the tank as I go. I believe those 3 inversions take about 6-7secs, so if you're inverting 5 times every 30secs, that's a lot higher ratio of agitation to sitting time. Not necessarily a bad thing, but maybe you need to accomodate it with shorter development times. Some experimentation might be in order. I think it's a good thing the System 4 tanks have a lot of air space (in the funnel area) so the developer gets to mix thoughly

This might be way of the mark, but is it a Kodak thing to agitate every 30secs (I use Ilford/Agfa developers) cause whenever anyone says they agitae every 30sec it's usually about a Kodak film (bit of a generalisation).

-- Nigel Smith (nlandgl@unite.com.au), December 17, 2001.

I guess I could have been clearer in my developing techniques. I follow the directions for the TMax film with TMax developer which states it needs more vigorous agitation. I tip upside down and give it one half turn, 5 times in ten seconds. This works well with 2 rolls, but not 1. I guess I'll need to shorten the development time for a single roll. Now all I have to do is figure out how much shorter, Or shoot more film! Thanks everyone. Janet

-- Janet (photojanet2256@cs.com), December 17, 2001.

Wow! I would never advise to have one roll in a 2 roll tank with only enough developer to cover the bottom reel but I think that's what I'm hearing. I used to see this a lot as a lab tech at a local JC and there were problems EVERY time. If you have 1 roll of film and always use a 2 roll or larger tanks, fill with empty reels so you are not sloshing all over and fill that sucker up as if you are developing a full tank. Develope at your normal time and temp. Other methods may work this one Will work. HTH W

-- Warren Allen (whatrix@home.com), December 22, 2001.

I completely second what Warren just wrote. Fill the tank, whether it's one roll or two. It's the only way you'll get consistent results. If you're worried about wasting chemistry, get a one reel tank.

-- Ted Kaufman (writercrmp@aol.com), December 23, 2001.

I disagree regarding consistancy. Maybe good advice for a beginner, but I'm going to keep doing it the same way I have for the last 20 years... The only time I've had a problem was when I mixed only enough developer for a 35mm roll and not the 120 I was developing and I can only blame operator error on that one!

-- Nigel Smith (nlandgl@unite.com.au), December 24, 2001.